Blogs

LED lights and the Periodic Table

Every LED light has a "band gap". Electrons are pushed into an empty orbital which is negative and then the positive end of the circuit attracts the electrons. As they go down in energy through the band gap, they emit light. The larger the band gap, the more energy, the smaller the wavelength and the closer to the "blue" end of the spectrum. So, the key is to try to control the band gap and thus control the color of light. 

Beyond the Curriculum

I always find this time of year quite harrowing. I am right in the middle of academic competition season with Olympiads in physics, chemistry, biology, and math. I have science bowl and ocean bowl along with bridge building all on the same day. Why do we do this to ourselves?

Ionic Covalent Compounds and Card Sorts

Ionic Covalent Card sort

Card sorts are a great way to achieve a number of classroom objectives.  They can be used as a review activity or they can be done during the middle of a lesson as a type of formative assessment. Sorts can encourage students to work with other students or can even be used as a type of exit ticket. I decided to use the strategy about two thirds of the way through a unit on covalent and ionic compounds and lewis structures. I knew there were items we did not cover in the sort but I was curious to see how they would approach these unknown topics.  

Chemical Connections to Climate Change

carbon dioxide absorbing IR light

It is becoming increasingly important for citizens to understand various concepts related to climate change and global warming. This post describes several chemical concepts that are pertinent to these issues, in the hopes that teachers of science and chemistry can introduce the topic of climate change into their classrooms and everyday discussions.

Mid-Year Reflections

concept map

It’s the end of one semester and the beginning of another. Final exam week. For the first time in my teaching career, I had my grades caught up and posted prior to the beginning of final exams. This gave me time to reflect and plan ahead.